Apparatus for heating metal articles of irregular shape



E. J. CARBO May 17, 1960 APPARATUS FOR HEATING METAL ARTICLES OF IRREGULAR SHAPE Filed Nov. 8, 1957 INVENTOR Edward J. Corbo %4 WITNESSES ATT RNEY APPARATUS FOR HEATING METAL ARTICLES OF IRREGULAR SHAPE Edward J. Carbo, Tow son, Md., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application November 8, 1957, Serial No. 695,255

7 Claims. (Cl. 2'664) Y Thisinvention relates to improvements in apparatus for cartridge case. hardening, and more particularly to improvements in such apparatus of the type employing induction heating. In addition, a new method of hardening is disclosed.

Prior art cartridge case hardening apparatus is characterized by a number of disadvantages. For example, it has been impossible toprovide for uniform hardening of the entire case area because of variations in the thickness of the-metal orvariations in the volume of metal to be heated) over the length of the cartridge case, and also it has been impossible to properly harden small arms cartridge cases at a high production rate.

The apparatus of the instant invention is especially suitable for hardening small arms steel cartridge cases where it is desired to through-harden the cases completely except, if desired, for approximately a short dis- 2, Fig. 2 is. a. view partially inside, elevation and partially schematic of the apparatus of Fig. 1.

Particular reference is made now to the drawings, in which like reference numerals are used throughout to designate like parts for a more detailed understanding of the invention. The apparatus embodying the'invent-ion includes generally a, hopper 10, Fig. 2, having a plurality of feed tubes 1:1, 12, 13 and 14, Fig. 1, for supplying cartridges in head-up positions to an escapement and feedingmechanism 15, hereinafter to be more fully described. Disposed beneath the escapement and feeding mechanism. 15 is a rotatable substantially circular plate member 16 preferably composed of a heatresistant non-magnetic metal and having a plurality of bores 17 at substantially equally spaced intervals around the periphery thereof near the;outer edge and-adapted to receive cartridge cases to be hardened from the feeding mechanism 15, four at a time. Disposed beneath a portion of the plate member 16' is a stationary cam member 18,'Fig. 2, and, cartridge case's deposited in the bores 17 at the 'escapement mechanism 15 bottom against the cam member 18, the bottoms of the cartridge cases moving along the uppersur-face of cam member 18 and upon reaching the ascending cam portion 19, the cart-ridgecases to be hardened are gradually moved upward where they become increasingly affected or heated by a heating coil 20. After being moved by movement of plate case-holding member 16. through the coil 20; to the right-hand end portion thereof as seen in Fig. 1, the cartridge cases have attained a sufiicient' temperature throughout their entire'mass; and a trap door 21 nortance, of, for example, one-half inch measured from the month end of the case, and where it is desired that the cases be processed, at a high production rate. 7

Apparatus embodying the invention comprises arotatable circular plate member having a plurality of bores at spaced intervals around the periphery thereof of a size suitable for receiving cases to l e-hardened. Feed-.

ing apparatus including a hopper feeds cases into the bores at one position of the plate member, and indexing means rotates the plate member in steps and moves the cases into positions adjacent coil induction heating means. A cam member cooperating with the plate member'provides that heating begins in the head portions of the cases beforeit begins inthe remainder of the cases. After heating throughout, cases are dropped into a quenching tank whence a belt-conveysthem to a delivery p n I r Accordingly, a primary object of the invention is to provide new and improved cartridge case hardening apparatus. 1 I

Another object of the invention is to provide' newand improved apparatus in which the handling of cartridge casesv to be hardened is automatic throughout the entire hardening process.

An additional object is' to provide induction heattreating apparatus for hardening cartridge cases in which the head portions of the cases are preheated; to provide for uniform hardening throughout. I

Still an additional object is to provide new andimproved induction cartridge case hardening apparatus in which novel means is employed for securing steel cartridge cases against imovement as a result of themagnetic field set up by the induction coil. 7

A further object-is to provide new" and improved cartridge case hardening apparatus in which soft spots in the side wall of the case resulting from insufficient heating or non-uniform quenching are eliminated.

mally located or disposed underneath the adjacent portion of the coil 20 and plate member 16 is withdrawn to the position shown in Fig. 1', allowing the four cartridge cases in the holes or bores above the trap door 21 to drop through four tubes,'one of which isshown in Fig. 2 and designated 22, each of the tubes 22 having a number of guide wires 23 attached to the lower end thereof, into a suitable quenching fluid 24. contained within a fluid container 25. Disposed within, the fluid container 25 is a belt; 26 moved by roller 27 and 28 mounted on shafts 29 and 30, respectively. Shaft 30 may be journalled for rotation with respect to roller 28, while roller 27 is splined orotherwise secured for rotation with shaft 29. Motor means 31, Fig. 1, coupled to shaft 29 isprovided for moving the belt 26. The cartridgecases dropped into -the quenching fluid 24 fall upon the belt 26 andare carried to the top of roller 27 where they arede'positedon the chute 32 for delivery in a hardened condition to a delivery point. I

As previously stated, the'plate member-16-is rotated in steps .or indexed, the plate member 16 being moved or rotated an angular distance corresponding substantially to the distance between four holes or bores 17, whereupon the plate member 16 is stopped briefly so that four additional cartridge cases to be hardened may be fed into four bores in the plate and four cartridge cases which have been heated to a predetermined dc? gree maybe dropped out by withdrawing trap door 21 for a brief interval. Thereafter trap door 21'is moved back into. position underneath-plate member 16, the plate member 16" is'moved again, being rotated in the same direction 'anequal distance, and the process of feeding four cartridge cases and discharging four cartridge cases with every indexing step is repeated.

To provide for the desired indexing movement of the plate member 16, a motor 33 is, provided which, may havesuitable means, not shown, for controlling or adjusting the speed thereof and is connected by shaft 34, coupling 35 and shaft 36 to an indexing mechanism 37. The aforementioned, motor 33 and indexing mechanism 3.7 are suitably mounted upon a supporting member 38,

and the indexing mechanism 37 is constructed and arranged to rotate the shaft 39 to which the aforementioned plate member 16 is secured for rotation, the desired angular distance, to thereafter stop the s'haft.39 a predetermined interval of time, and to rotate the shaft 39 and the attached plate member 16. again the preselected angular distance, this process being repeated as long as the motor 33 is energized.

In order that the apparatus may function properly, the operation of the escapement and feeding mechanism 15 and the operation of the aforementioned trap door 21 are synchronized with the step movement of the plate member 16. This is provided for by additional shafts 40 and 41 coupled at 42 to the main drive shaft 39; shaft 41 is connected to moving means 43 of any convenient design which is connected by coupling members 44 and 45 and arm 46 to the aforementioned trap door 21, for moving the trap door 21 outwardly to the position shown in Fig. 1 when the plate member 16 comes to a stop, maintaining the trap door 21 in its outward position as indicated in Fig. 1 for a preselected interval of time suiiicient to allow the four cartridge cases in the bores immediately above to drop into the tubes 22, and thereafter to return the trap door 21 to a position underneath the adjacent bores in the plate member. 16, that is, to a position where the trap door 21 constitutes in effect an extension of the cam member 18.

The aforementioned shaft 40 is coupled to moving means 47 of any convenient design which is coupled by elements 48, 4? and 50 to the aforementioned escapement and feeding mechanism 15, the escapement and feeding mechanism 15 being of any convenient design and constructed and arranged to control suitable apparatus, not shown, for example, shutter apparatus therein to discharge four cartridge cases into the four adjacent and alignedbores of plate member 16 while the plate member 16 is stationary, and to hold back thestacks of cases in tubes 11-14 inclusive and prevent the further discharge of cartridge cases while the plate member 16 is in motion. Elements 43, 45, 47 and 49 may include gear means, not shown, if desired.

' Particular reference is made now to Fig. 1 where means for maintaining the cartridge'cases to be hardened in upright positions in the bores 17 in plate member 16 is seen to comprise a plurality of spider arms 51 composed of a material having a preselected degree of stiffness and resiliency, the spider arms 51 being secured by mounting means 52 for rotation with the aforementioned shaft 39. Each of the spider arms 51 has a pin 53 attached to the end thereof, the pin having a head portion and a shank portion 54. The number of spider arms 51 and accordingly the number of pins 53 is equal to the number of bores 17 in the plate member 16, and the spider arms 51 are'disposed in alignment with the bores 17 and are provided so that the pins on the ends thereof may engage the heads of the cartridge cases to be heated which are disposed in certain of the bores 17 and maintain the cartridge cases in substantially upright positions, and further oppose movement of the cases in response to magnetic forces created by energization of the coil 20. To provide for the free rotation of all of the spider arms 51 and their attached pins 53, a circular cam member 55 is providedhaving a portion 56 which tapers downward in the direction of rotation of plate member 16 and a portion 57' which tapers upward in said direction of rotation, the spider arms 51 and their associated pins 53 being cammed up over the top of the escapement mechanism 15, as viewed in Fig. 2, the aforementioned cam member 55 being suitably mounted by arms 58 so that the cam member 55 remains in a stationary position. As the cartridge cases 59 are moved upward by the aforementioned upwardly tapering portion 19 of cam member 18, the spider arms descend downward over the aforementioned taper-down portion 56 of cam 55 and the shank portions 54'of the pins 53 engage the holes in the heads 60 of the cartridge cases 59, holding the heads 60 and the cases 59 in upright positions as the cases 59 move through a portion of the heating coil 20. At a point or angular position corresponding substantially to the far or upper end of the trap door 21 as seen in Fig. l, the taper-up cam portion 57 moves the spider arms 51 upward again so that they may ultimately pass freely over the escapement and feed mechanism 15' Without their movement being retarded.

The aforementioned spring spider arms 51 and the attached pins 53 also provide a slight push to the adjacent four cases upon opening the trap door 21, to assist in their dropping into tubes 22.

In order to hold the cartridge cases 59 in upright positions before the heads 60 thereof .are engaged by the aforementioned pins 53, a pair of preferably parallel wires 61 and 62, such, for example, as wires made of a heat-resistant material, the wires being of suflicient rigidity, are provided and engage the head portions 60 in grooves 63 between the heads 60 and the remainder of the cartridge cases, and thereby hold the cartridge cases 59 in upright positions with their lower ends ad jacent cam member 18 until the heads 60 thereof are engaged by the aforementioned pins 53. Thecnds of wires 61 and 62 may be attached to cam member 18,,as shown.

A suitable source of alternating current potential 64 is provided and is connected by leads 65 and 66-:to the aforementioned coil 20, for providing for the induction heating of the cartridge cases 59 to. the desired temperature, for example, 1800 to-l900 F. a

Any suitable means, not shown, maybe employed for mounting and holding the aforementioned stationary cam member 18 in the desired position.

Whereas a coil 20having a certain shape and number of turns has been shown, it should be understood that a heating coil having any suitable shape and any desired number of turns may be employed, it being recalled that because of the greater mass in the head portion of the cartridge cases, it is desirable to apply heat to this portion of the case before, or at a greater rate than, heat is applied to the remainder of the cartridge case, and accordingly, the aforementioned ascending cam portion 19 is provided to gradually move the entire body of the cartridge case into position to have the temperature thereof raised by the coil 20 The method of practicing the invention, briefly stated, includes feeding cartridge cases to'behardened 'into a rotatable case holder, rotating the case holder in steps to move the cases, induction heating the cases at preselected positions in their paths of movement, dischargmg the cases after heating from the case holder, rapidly uenching and cooling the discharged cases, and conveymg the cooled cases to a delivery point. r

In the practiceof 'the invention, in adjusting the a paratus of Figs. 1 and 2 for proper operation, the speed of movement of plate member 16 may be manually adusted by varying the speed of motor 33 in accordance with the degree of heating provided by coil 20 and the size and material of the shell casings to be heat-treated or hardened.

If desired, any suitable means, not shown, may be provided for adjusting the energization of coil 20, for example, a rheostat, not shown, in the DC fieldof; an inductor-type generator supplying the alternating current potential.

If desired, plate member 16 maybe made easily removable from the apparatus so that other plate members having different size bores to accommodate other calib'er cartridge cases may be readily interchanged therewith. The various elements of the apparatus may have any suitable dimensions, the drawings being merely illustrative; any suitable means, not shown, may'bc provided-for mounting the various parts of the apparatus in desired positions with respect to each other. 4

Belt 26 may be moved at any convenient speed, for

exam le 30 feet per minute.

Source of electromotive force '24i may have any cohvenient frequency, for example, 10,000 cycles per second. Whereas the invention has been shown and described with respect to a preferred embodiment thereof which "gives satisfactory results, it should be understood that changes may be made and equivalents substituted without departing from the spirit and scope of the invention.

I claim as my invention:

1. In cartridge case hardening apparatus, in combination, a rotatable plate having a plurality of bores of substantially equal diameter substantially equally spaced at intervals around the periphery thereof, means operatively connected to said plate for rotating the same, arcuate cam means disposed underneath at least a portion of said plate at a distance therefrom which varies over at least a portion of the length of the cam means, means disposed in predetermined position with respect to said plate for feeding cartridge cases to be hardened into the bores in said plate, coil means disposed in predetermined position with respect to said plate, said coil means being constructed and arranged to heat by induction cartridge cases,

disposed adjacent thereto, said cam means and coil means being constructed and arranged to provide that cartridge cases mounted in the plate and moving therewith have their head portions heated first and are heated thereafter substantially uniformly in the body portions, and means operatively connected to the plate and disposed in predetermmed position with respect thereto for causing the discharge of cartridge cases after heating from the plate.

2. In cartridge case hardening apparatus, in combination, rotatable plate means having a plurality of bores of substantially equal diameter at substantially equal. spaced intervals around the periphery thereof, means disposed in predetermined position with respect to the plate means for feeding cart-ridge cases to be hardened into said bores at a preselected rate, means operatively connected to the plate means for rotating the same, heating means disposed in predetermined position with respect to the plate means and adapted to heat by induction cartridge cases carried into positions adjacent thereto as the plate means rotate, quenching means, means operatively connected to the plate means for discharging heated cases into the quenching means, and means including a plurality of resilient arms having a plurality of pins on the ends thereof respectively for engaging at least some of the cartridge cases during at least a portion of their travel around'the periphery of the plate means for holding the cartridge cases in substantially upright positions in said bores.

3. Cartridge case hardening apparatus comprising, in combination, a rotatable plate member having a plurality of bores of substantially equal diameter at substantially equally spaced intervals around at least a portion of the periphery thereof, feeding means including hopper means disposed in predetermined position with respect to said plate member and constructed and arranged to feed cartridge cases to behardened into the bores of said plate member as the plate member rotates, means operatively connected to the plate memberfor rotating the same, coil means disposed inpredetermined position with respect to said platemernber and constructed and arranged to heat; by induction cartridge cases carried by the moving plate member into positions adjacent the coil means, quench tank means including a quenching fluid disposed below at least a portion of said plate member, means operatively connected to the moving means for discharging the heated cases into the quench tank means after heating by coil means, and belt means disposed at least partially in the quench tank means and adapted to receive the dfopp'ed case's, saidbelt'meaiis being massacred and arranged to bring the cooled cartridge cases t6 a aefiver point. e r

4. Cartridge case hardening apparatus comprising, combination, rotating case holdingm'eans constructed and arranged to receive cartridge cases'lto be hardened at "a first position in the path of rotation thereof and to discharge the cases at a secondposition in 'the'p'a'thof rota"- tion thereof, "coil means located near said second position for heating cases by induction as they approach said secend position, means including a plurality of spider arms having pins attached to the ends thereof for engaging the cartridge cases and holding the cartridge cases in proselected positions on the case holding means as the case holding means rotates from the first position to the second position, feeding means including hopper means disposed in predetermined position with respect to the case bold ing means and constructed and arranged to feed cases into the case hold-ing means at the first position, quenching means disposed in predetermined position with respect to said second position, means disposed in predetermined po-. sition with respect to thetcase holding means at said second position for removing heating cases from :the case holding means and depositing the removed cases in the quenching means, and conveyor means mounted in predetermined position with'respect to the quenching means and constructed and arranged to bring the cooled cartridge. cases after quenching to a delivery point. 7

5. Cartridge case hardening apparatus comprising, in combination, rotatable cartridge case receiving means constructed and arranged to receive at least one cartridge case to be hardened while the case receiving means is in a first setting and to discharge the cartridge case while the case receiving means is in a second setting, coil case heating means disposed adjacent the case receiving means near the second setting, feeding means including hopper means for feeding cases to be hardened to the case receiving means at the first setting, case discharge means including quenching means operatively connected to the case receiving means at the second setting, conveyor means operatively associated with the quenching means, moving means operatively connected to the case receiving means, to the feeding means, and to the case discharge means for providing for the feeding of cases to the case receiving means and the discharge of the last-named cases from the case receiving means, and means including a plurality of spider arms having pins on the ends thereof and adapted to engage the heads of the cartridge cases and to maintain the cartridge cases in predetermined positions as the cartridge case receiving means rotates cases from the first setting to the second setting.

6. In cartridge case hardening apparatus, in combination, a rotatable plate having a plurality of bores of substantially equal diameter located at substantially equally spaced positions around at least a portion'of the periphery quenching means operatively connected with said plate,

said quenching means. including a cooling fluid and being constructed and arranged to provide for the discharge of cases after heating from the plate into the cooling fluid after the cases having been carried through at leasta portion of the coil means. I 1

7. In cartridge case hardening apparatus, in combination, moving cartridge casereceiving means adapted to receive a cartridge case at a first position and to carry the cartridge case to a second dischargeposition, coil means disposed in predetermined position with respect to the case receiving means and constructedand arranged to heat the case as it moves tothe second position, feeding mea'ns operatively connected to the case receiving means for feeding the cartridge case to be hardened to the case receiving means at;t he first position, quenching means pperativ e ly connected tc the case receiving means and constructed and'arranged to receive the heated case discharged by the case receiving means at the second position, and means including a spider arm having retaining means on the end thereof, said retaining means being adapted to engage the head of the cartridge case while on said case receiving means and to retain the cartridge case in a preselected position during at least a portion 0f its travel on the case receiving means.

References Cited in the file of this patent UNITED STATES PATENTS Gilman July 13, 1926' Goodridge Jan. 12, 1943 Stevens Apr. 2, 1946 Hoyler et al. May 1 7, 1 949 Foxx Degc. 2, 1952 'Peters et val -L- Apr. 7, 1953 Lyon Dec. 6, 1955 

